The present invention relates to a work performing appliance of the type having means for facilitating movement of the appliance body along a floor surface when pulled by a hose used to perform the work of the appliance and, more particularly, apparatus for distributing the pulling forces applied through the hose to the appliance to reduce the tendency of those forces to tip over the appliance.
The present invention was developed to solve a tipping problem encountered with heavy duty vacuum cleaners of the upright drum or cannister type. Accordingly, the apparatus will be described as used in conjunction with, and the background of the invention will be given with reference to, a vacuum cleaner of this type. It should, however, be appreciated that the apparatus can be successfully employed with other appliances.
Upright drum vacuum cleaners are particularly adapted for drawing heavy or large debris commonly found in garages, workshops, etc. Some of these units are also adapted to vacuum standing water. Elongate, flexible intake hoses are provided to selectively direct the suction forces from a vacuum cleaner body throughout an area around the body. In order to clean an area beyond the reach of the flexible hose, the vacuum cleaner body itself must be moved to another location.
It is known to provide the vacuum cleaner body with a set of casters or the like so that it may be rolled across a floor surface to different areas to be cleaned. With the provision of casters, the vacuum cleaner body is automatically pulled behind the user into a new location as soon as the user, in trying to reach a surface beyond the flexible extent of the hose, applies a pulling force through the hose to the body. Ideally, through this natural vacuuming action of the user and the provision of means to facilitate sliding or rolling motion of the body across a floor surface, the user need not return to the vacuum cleaner body and carry or push it to a new location each time it is desired to clean an area beyond the extent of the hose. This naturally increases efficiency, reduces user work and consequently enhances user satisfaction.
Unfortunately, because of various characteristics of the vacuum cleaner body dictated by functional design requirements, pulling the intake hose frequently tips the vacuum body over on its side, and the advantages otherwise enjoyable through the provision of casters or the like are lost. First, a heavy electric motor is mounted at the top of the upright drum, which makes the vacuum cleaner body top-heavy and unstable when tipped away from its normal vertical orientation. Functional requirements also dictate that the intake opening to which the one end of the intake hose is connected, and thus where the pulling forces are applied, be located adjacent the top of the drum. Each time the vacuum cleaner body is tipped over on its side, the user must of course return to the vacuum cleaner body to put it back in an upright position before work can be resumed. Further, if the drum is filled with water or fluid, like material such as dust, tipping the drum may result in escape of the fluid through the vacuum outlet opening and onto the floor surface being cleaned. As the drum fills with debris, the vacuum body becomes less top-heavy, but the increased weight increases the static friction forces between the floor surface and the casters resisting movement in the direction of pulling forces, and thus the tendency of the vacuum cleaner body to tip is not substantially reduced.